Exploring Brain Entropy Across the Adult Lifespan by Using a Novel Rapid Quantitative Magnetization Transfer MRI

Motivation: Identifying biomarkers of brain aging is important for understanding the mechanisms of aging-related changes that are potentially indicative of underlying neurological conditions. Goal(s): We aimed to identify in vivo biomarkers sensitive to aging-associated brain changes in healthy subjects using a novel qMT MRI. Approach: Rapid hybrid-state qMT imaging combined with an unconstrained 2-pool model was performed with 1-mm isotropic resolution and whole-brain coverage. The entropy of qMT parameters was calculated within ROIs, and a correlation analysis was performed between entropy and age. Results: Significant correlations between the entropy of qMT parameters and age were found across the brain. Impact: Our demonstration of qMT brain entropy as a sensitive indicator of normal aging-associated changes throughout the brain provides a potential quantitative biomarker that can be utilized to detect underlying neurological conditions linked to aging, enabling timely intervention.